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What's a good reliable generator, only worried about the generator part

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Jon Anderson

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Nov 21, 2009, 12:59:50 PM11/21/09
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For my eventual move to Oz, I will be building my own motor/generator to
power those tools that cannot be converted to 3phase. Don't plan to run
many items at once, I'm thinking about maybe a 4kw generator.

What's a good reliable generator at the output end? Going to try to find
one with a bad engine, but want to make sure the other half will last a
while given the expense of having a replacement shipped over....
And yeah, I'm planning on taking spare parts for it.


Jon

Jim Wilkins

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Nov 21, 2009, 1:06:22 PM11/21/09
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Karl Townsend

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Nov 21, 2009, 1:11:47 PM11/21/09
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"Jon Anderson" <jande...@comcast.net> wrote in message
news:fUVNm.62201$Vr1....@en-nntp-01.dc1.easynews.com...

May not fit your needs, but conside a WinPower PTO generator. They are built
to last forever and a small tractor powers them. Bet they got tractors in
OZ. I've had mine thirty years and had to add oil once, and then replace the
tires cause they rotted out. Mine is 15KW but it takes my large tractor if I
need that much. I've run the house lights with an old 8N ford tractor.

Karl


RoyJ

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Nov 21, 2009, 1:54:08 PM11/21/09
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I think Onan is (was?) the king of good gensets. Their 1800 rpm versions
really nice. But EXPENSIVE parts.

If you buy a regular genset with engine, keep in mind that almost all of
them have only one bearing on the generator section. they use a tapered
shaft coupling to hook it to the engine, use the engine output bearing
to support one end of the rotor. This means that swapping out a bad
engine is not anywhere as easy as you might expect. You need the
specific crankshaft that came with the original setup. If you trash an
engine badly, you have to buy the new engine AND a new crankshaft with
the correct taper (almost impossible to get the new engine with the
correct taper)

The generator itself is pretty reliable. If the windings are big enough
to handle the loads, there isn't much else. The bearings of course, a
couple of diodes, brushes if they are there, that's it.

Karl mentioned the PTO setup. A great way to go.

Jon Anderson

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Nov 21, 2009, 2:43:01 PM11/21/09
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Karl Townsend wrote:

> May not fit your needs, but conside a WinPower PTO generator. They are built
> to last forever and a small tractor powers them.

Might be overkill, but sure sounds like it's worth looking into! Going
to be shipping at least one container, so size isn't a huge issue.
I sure like the 'built to last forever' part!

Thanks,

Jon

Larry Jaques

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Nov 21, 2009, 2:53:58 PM11/21/09
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On Sat, 21 Nov 2009 09:59:50 -0800, the infamous Jon Anderson
<jande...@comcast.net> scrawled the following:

Why don't you swing by Chiwan on the way over to Oz and pick up an
entire unit, Jon? ;)

--
We have too many high sounding words, and too few actions that correspond
with them. -- Abigail Adams, letter to John Adams, 1774

co_f...@yahoo.com

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Nov 21, 2009, 3:21:34 PM11/21/09
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Don't generators in OZ turn opposite to US?

Paul

Karl Townsend

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Nov 21, 2009, 3:26:20 PM11/21/09
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"Jon Anderson" <jande...@comcast.net> wrote in message
news:VoXNm.257331$Jp1.1...@en-nntp-02.dc1.easynews.com...

if you're anywhere near the midwest, virtually every large farm acution has
one. They very seldom bring $1K, often 1/2 that.. many auctioneers are going
online so you wouldn't have to waste the day waiting for it to sell.

Karl


Ecnerwal

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Nov 21, 2009, 3:33:05 PM11/21/09
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In article <fUVNm.62201$Vr1....@en-nntp-01.dc1.easynews.com>,
Jon Anderson <jande...@comcast.net> wrote:

> What's a good reliable generator at the output end? Going to try to find
> one with a bad engine, but want to make sure the other half will last a
> while given the expense of having a replacement shipped over....

Northern Lights. Finding one with a bad engine may be a problem - the
whole unit works pretty reliably, but I guess you might find one with an
owner that didn't change the oil or something. They make land-based
units, but are more prevalent as a marine unit. That's a good thing for
worldwide parts availability.

Makes little difference (land or marine) if you are just grabbing the
generator end. I can make a few suggestions about using a marine unit on
land if you went that route, as I am doing that.

IMHO, 1800 or 1200 RPM (for 60 hz) units are the only reliable ones out
there - 3600 tend to have short lifetimes.

--
Cats, coffee, chocolate...vices to live by

ATP*

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Nov 21, 2009, 3:54:48 PM11/21/09
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"Ecnerwal" <MyName...@ReplaceWithMyVices.Com.invalid> wrote in message
news:MyNameForward-A2F...@mail.eternal-september.org...

I've had a 3 KW Yanmar diesel for about twenty years, they're pricy but last
forever and use very little diesel. Noisy as hell though, it definitely
sounds like a diesel. Larger units have more sound deadening and larger
mufflers.


N Morrison

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Nov 21, 2009, 4:50:01 PM11/21/09
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On Nov 21, 9:59 am, Jon Anderson <janders1...@comcast.net> wrote:

> For my eventual move to Oz, I will be building my own motor/generator to
> power those tools that cannot be converted to 3phase.

Why? They have AC in Australia you know. 415 V - 3 phase, 240 V single
phase, all 50 cycles. How will a generator help?


Jon Anderson

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Nov 21, 2009, 5:12:41 PM11/21/09
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Larry Jaques wrote:

> Why don't you swing by Chiwan on the way over to Oz and pick up an
> entire unit, Jon? ;)

GACK!

I'm trying to accumulate as much good ol' USofA tools as I can before I
go. I looked up the units Karl suggested, serious overkill, but if I can
find one cheap enough...


Jon

Jon Anderson

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Nov 21, 2009, 5:14:35 PM11/21/09
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Ecnerwal wrote:

> Makes little difference (land or marine) if you are just grabbing the
> generator end. I can make a few suggestions about using a marine unit on
> land if you went that route, as I am doing that.
>
> IMHO, 1800 or 1200 RPM (for 60 hz) units are the only reliable ones out
> there - 3600 tend to have short lifetimes.

Suggest away! Since I'll belt drive the generator from the 50hz motor, I
can handle any rpm, but would like to stay with lower rpm stuff.

Thanks,

Jon

Bruce L. Bergman

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Nov 21, 2009, 5:57:01 PM11/21/09
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Yes, but some tools are built for US Power Only - for residential
straight 120V 1-Ph or 120-240V 1-Ph center-tap neutral, and for light
industrial it could be 120/208V Wye 3-Ph, 240V 3-Ph Delta or Open
Delta, 277/480V 3-Ph Wye, 480V 3-Ph Delta. All at 60 Hz.

Some gear would be expensive or imposible to convert to Austrailian
power directly. AIUI, you use straight 240V 1-Ph or 240/415V Wye
3-phase. AT 50 HERTZ, which is the big bugaboo for electronics gear
and certain heavy machinery that can't handle 50-Hz natively.
Transformer cores and motor laminations have to be built differently
to handle both.

You can use a bank of transformers to drop 240V to 120V or 415 to
240V, or boost 415V to 440V, but changing the frequency with enough
energy to run machine tools is a huge issue - that calls for specially
built Motor-Generator sets that have a gearbox or rotating field to
boost the frequency, or a big Variable Frequency Drive just to bump
the frequency up.

There is gear specifically built to run on "World Power" I.E. it is
not frequency sensitive and has multiple input voltage taps to handle
almost anything you throw at it. But they are the exception in the
marketplace, and rarely found used at reasonable prices.

(You have to find a seller who doesn't know what they have, or is
highly motivated to sell fast.)

If he has an engine driven generator set, it's simple to make 60-Hz
power to run the shop gear. Just feed it fuel and air, and the
occasional oil change. The tractor driven PTO generators are even
easier, because the Prime Mover can be changed easily when it breaks
or wears out.

--<< Bruce >>--

Jim Wilkins

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Nov 21, 2009, 7:28:27 PM11/21/09
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On Nov 21, 5:57 pm, Bruce L. Bergman <bruceNOSPAMberg...@gmail.com>
wrote:
> ...
Can you change a 50Hz gas or Diesel generator to 60Hz?

jsw

Bill Janssen

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Nov 21, 2009, 7:37:05 PM11/21/09
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An marine unit or an RV unit makes less noise. That may be advantage for
your use.

Bill K7NOM

Bruce L. Bergman

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Nov 21, 2009, 8:36:10 PM11/21/09
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I suppose you could if it was originally designed as a 60Hz unit and
modified to 50Hz for the export market. Could be as simple as
tweaking the governor setting from 1500 RPM (50Hz on a 4-pole
generator) back up to 1800 RPM.

Problem being, the export units might not be wound to put out 120V
or 120/240V 1Ph or 120/208V 3Ph. They'll wind them at the voltages
the export market usually wants - 240V and 240/415V.

--<< Bruce >>--

bob prohaska's usenet account

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Nov 21, 2009, 8:51:02 PM11/21/09
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Jon Anderson <jande...@comcast.net> wrote:
>
> Suggest away! Since I'll belt drive the generator from the 50hz motor, I
> can handle any rpm, but would like to stay with lower rpm stuff.
>
Ok, I'll bite.

How about an ordinary variable frequency drive? They take the line
AC, rectify it to DC and invert it to whatever frequency and voltage
you want. All solid state, and relatively efficient compared to a
rotary converter. In the low tens of horsepower they're common, I'm
not sure how big they come.

bob prohaska

Bruce L. Bergman

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Nov 21, 2009, 8:56:03 PM11/21/09
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If you want to make an electric motor driven motor-generator, I hope
you are made of money - that's going to cost a ton to run, when you
figure in the inefficiency of buying the power from the grid. Just
think about it - to start the main motor on a 10 HP machine your
converter needs to be (rough guess) 40 HP or better...

And belts for the step up drive (1500 RPM electric motor to 1800 RPM
generator head) will have to be adjustable, or your frequency is going
be way off - and with belts it will still sag and surge pretty bad.
You can't just adjust the throttle...

You could hard-couple the motor and generator with a Lovejoy
Coupling IF you can find a rotating field generator head
("Electronically Commutated") or the "Inverter" style (Honda EU line)
where engine RPM is not the frequency timebase.

A conventional genset with a diesel prime mover will make a lot more
sense. And the PTO Drive generator driven off a locally available
tractor is a close second.

--<< Bruce >>--

Larry Jaques

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Nov 21, 2009, 9:09:37 PM11/21/09
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On Sat, 21 Nov 2009 14:12:41 -0800, the infamous Jon Anderson
<jande...@comcast.net> scrawled the following:

>Larry Jaques wrote:


>
>> Why don't you swing by Chiwan on the way over to Oz and pick up an
>> entire unit, Jon? ;)
>
>GACK!

I thought you'd like that. <snicker>


>I'm trying to accumulate as much good ol' USofA tools as I can before I
>go. I looked up the units Karl suggested, serious overkill, but if I can
>find one cheap enough...

Yeah, with all the machines you have now, I guess another ton or two
won't hurt.

Jon Anderson

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Nov 21, 2009, 9:37:47 PM11/21/09
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bob prohaska's usenet account wrote:

> How about an ordinary variable frequency drive? They take the line
> AC, rectify it to DC and invert it to whatever frequency and voltage
> you want.

Not looking for phase conversion, I'll be using inverters for 3 phase
machinery not rated for 50hz (oddly, my Bridgeport is, both Hardinge
lathes and the Chevalier are not).

What I'm looking to run are things like my Baldor carbide grinder, drill
sharpener, and the many hand power tools like drills, grinders, circular
saws, vacuum pump, etc. Would get pennies on the dollar to sell here,
and have to pay top dollar there. A motor generator would allow me to
run anything and everything not covered by inverters.


Jon

Jon Anderson

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Nov 21, 2009, 9:52:44 PM11/21/09
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Larry Jaques wrote:

> Yeah, with all the machines you have now, I guess another ton or two
> won't hurt.

Weight's not my issue, weight-wise everything would easily be handled by
a single 20' container. Volume is the issue. Would love to just use a
40' container, but storage there would be an issue. Wife's got friends
that would store a 20' until I had somewhere to put things, but not a
40. And, you've seen my driveway, loading a 40'er here and getting it
onto a truck would not be trivial by any means! Man, the thought of
winching machines uphill into a container with a wooden floor.... :(

Still working on my 3D CAD loadout trying to see just what I might be
able to squeeze in.


Jon

Ecnerwal

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Nov 21, 2009, 9:54:53 PM11/21/09
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In article <%CZNm.230924$Xw3....@en-nntp-04.dc1.easynews.com>,
Jon Anderson <jande...@comcast.net> wrote:

It's mostly regarding the motor/cooling setup - if you're only using the
generator end (which I suspected, but wasn't 100% sure of until you
posted more) there's little difference, at least with NL - the gen-end
is air cooled. With nearly all generator ends that are designed to
close-couple to an engine, you'll need to make up a support plate with
bearing to belt-drive them, since they use the motor bearing for that
end of the generator.

The main factor in dealing with a marine setup on land is getting rid of
the heat - there's no built-in radiator. This can be good and bad. The
unit itself is smaller and simpler without the radiator hanging off of
it, and the heat can be mostly sent elsewhere - in my case, into the
floor during heating season, into hot water in any season, and out to
the air only when there's too much heat - gets a bit more use out of the
same fuel dollar. Also means the genset is not a complete packaged unit
that only ties into the electric line - for my use/mindset, that's not
bad, for some, it is.

Depending exactly what you are dealing with, the VFD suggestion deserves
examination.

A third possibility (but pretty expensive) would be to have an
Australian battery charger feeding a DC battery bank feeding a US
voltage inverter, preferably of the true sine wave flavor - that would
work for more things than the VFD might, given that VFDs don't pay much
attention to making sine waves, as I understand them from other
discussions we've had here. It handily gets around Bruce's issues with
trying to frequency convert via belt drive, or indeed involving motors
in the process at all. It's quite do-able at the 4KW level, but does
take a chunk of change.

I suppose the other potential bug-bear might be what sort of hassles you
might get from Australian electrical inspection of whatever you do.

Gunner Asch

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Nov 21, 2009, 10:02:01 PM11/21/09
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On Sat, 21 Nov 2009 09:59:50 -0800, Jon Anderson
<jande...@comcast.net> wrote:

>For my eventual move to Oz, I will be building my own motor/generator to
>power those tools that cannot be converted to 3phase. Don't plan to run
>many items at once, I'm thinking about maybe a 4kw generator.

Cant be converted to 3 phase? SImply use 2 of the 3 leads.

Or are you looking for a 3ph genny?


>
>What's a good reliable generator at the output end? Going to try to find
>one with a bad engine, but want to make sure the other half will last a
>while given the expense of having a replacement shipped over....
>And yeah, I'm planning on taking spare parts for it.
>
>
>Jon

"Aren't cats Libertarian? They just want to be left alone.
I think our dog is a Democrat, as he is always looking for a handout"
Unknown Usnet Poster

Heh, heh, I'm pretty sure my dog is a liberal - he has no balls.
Keyton

Jon Anderson

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Nov 21, 2009, 11:18:08 PM11/21/09
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Gunner Asch wrote:

> Cant be converted to 3 phase? SImply use 2 of the 3 leads.

By that, I meant converting by changing out the motor.

All existing 3 phase stuff gets inverters unless rated 50hz
Stuff like the drill press, Roll-in saw, etc., get 3ph motors
w/inverter, or locally sourced 50hz motors.
The motor/generator setup is for all the rest of my stuff. Mostly brush
motor tools which would work with just a transformer, but some induction
motor stuff too, like the Baldor.

I have one customer more than willing to deal with me from down under.
Shipping is no biggie, I could put $5k worth of stuff into a medium flat
rate Priority box. But I need both CNC machines to do the work. If his
sales meet projections, work for him alone would easily pay my shipping
costs within 2 years. Just don't have the $$ to ship yet.

Working on my 3D loadout, and I can already see there's no friggin way I
get everything into one 20' container.
This would all be SO much easier if I just sold all the machinery here.
But making and fixing things is so much a part of my life I just cannot
envision not having them. Sigh...


Jon


Gunner Asch

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Nov 22, 2009, 12:20:14 AM11/22/09
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Excellent idea!!

Gunner

Gunner Asch

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Nov 22, 2009, 12:22:41 AM11/22/09
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Are the things you are wanting to run, 60 hrtz only and are they single
or 3 phase?

Gunner, missing part of the puzzle.

jbsl...@gmail.com

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Nov 22, 2009, 7:02:18 AM11/22/09
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On Sat, 21 Nov 2009 18:37:47 -0800, Jon Anderson
<jande...@comcast.net> wrote:

I assume that you do know that any 60 hertz motor will run on 50 hertz
current albeit at a slower speed. There will be a slight loss in
maximum available power due to the lower frequency, but at lower
loading you should experience no problems.
Regards,

J.B.

jbsl...@gmail.com

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Nov 22, 2009, 7:06:06 AM11/22/09
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Just add a 1::2 transformer. South East Asia is full of them as most
of the countries have/had both European and U.S. stuff for years.
(not so much U.S. stuff any more :-)
Regards,

J.B.

dca...@krl.org

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Nov 22, 2009, 9:15:06 AM11/22/09
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On Nov 21, 5:59 pm, Jon Anderson <janders1...@comcast.net> wrote:
> For my eventual move to Oz, I will be building my own motor/generator to
> power those tools that cannot be converted to 3phase. Don't plan to run
> many items at once, I'm thinking about maybe a 4kw generator.
>
> What's a good reliable generator at the output end? Going to try to find
> one with a bad engine, but want to make sure the other half will last a
> while given the expense of having a replacement shipped over....
> And yeah, I'm planning on taking spare parts for it.
>
> Jon

I think you are looking for something like this.

http://cgi.ebay.com/NEW-ST-10KW-GENERATOR-HEAD-1-Phase-Diesel-Gas-Engine_W0QQitemZ220513914951QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item3357a75047

Search on " generator head ST "

However these are made in China and are probably available in
Australia.

Dan

Jon Anderson

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Nov 22, 2009, 1:42:50 PM11/22/09
to
Gunner Asch wrote:

> Are the things you are wanting to run, 60 hrtz only and are they single
> or 3 phase?

Yes. 3 phase is common there and I'm likely to end up with my shop in a
commercial space anyway. Phase conversion is NOT the issue.

It's running the few 60hz induction motor items that I'm looking at
covering. And as I'm looking at the cost of the generator setup for just
a few items, I'm starting to wonder if it really -is- cost effective....
Most of the hand tools could be covered by a simple transformer really.

Anyone have a 3 phase Baldor carbide grinder they want to trade for a
110v model? For the little use it gets, I'm starting to think 50hz
probably won't be an issue.


Jon

Ignoramus30959

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Nov 22, 2009, 1:44:55 PM11/22/09
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I have a delta carbide grinder, 3 phase.

i

Jon Anderson

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Nov 22, 2009, 1:48:12 PM11/22/09
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dca...@krl.org wrote:

> I think you are looking for something like this.

Yeah, that's getting there. I did find something similar at Northern
Hydraulics last night, but they were 3600 rpm. If this guy can get one
in around a 4kw output, I think I'd go for it. Only has the one listed,
but I asked about getting a smaller one.

Thanks!


Jon

Jon Anderson

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Nov 22, 2009, 2:29:29 PM11/22/09
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Ignoramus30959 wrote:

> I have a delta carbide grinder, 3 phase.

Hmm, shipping cross country probably isn't going to be cheap. I'll keep
that in mind though if I decide to forget about a motor/generator.

Thanks,

Jon

dca...@krl.org

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Nov 22, 2009, 3:43:11 PM11/22/09
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On Nov 22, 6:48 pm, Jon Anderson <janders1...@comcast.net> wrote:

There have been other vendors on ebay. I have seen 3 phase generator
heads and also one that have a output for use as a welder. Just do
not see them today.

Dan

Gunner Asch

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Nov 22, 2009, 5:04:08 PM11/22/09
to

Stick a small car engine on it with a belt idling at 900 rpm and a 1:2
pully ratio and one is golden.

Gunner

Gunner Asch

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Nov 22, 2009, 5:04:45 PM11/22/09
to


The price is right. And you can use it for running the house if the
power goes out.

jbsl...@gmail.com

unread,
Nov 22, 2009, 7:43:28 PM11/22/09
to
On Sun, 22 Nov 2009 10:48:12 -0800, Jon Anderson
<jande...@comcast.net> wrote:


Mechanically the generator itself doesn't care what RPM it turns at,
Other then possibly accelerated bearing wear which is minimal with
ball/roller bearings. The gumph about 1800 RPM vis-a-vis 3600 was
mostly heard from the marine users and was mainly worry about engine
life and noise.

Regards,

J.B.

RoyJ

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Nov 23, 2009, 12:22:06 AM11/23/09
to
Not really. An 1800 rpm generator will be a 4 pole unit, a 3600 rpm
generator will be a 2 pole unit. A 4 pole, 1800 rpm unit is usually
MUCH quieter than the 2 pole versions. And engine life at 1800 rpm is on
the order of 5x to 10x the life at 3600 rpm.

Bruce L. Bergman

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Nov 23, 2009, 3:18:52 AM11/23/09
to
On Sun, 22 Nov 2009 14:04:08 -0800, Gunner Asch
<gun...@NOSPAMlightspeed.net> wrote:

>On Sun, 22 Nov 2009 06:15:06 -0800 (PST), "dca...@krl.org"
><dca...@krl.org> wrote:
>
>>On Nov 21, 5:59�pm, Jon Anderson <janders1...@comcast.net> wrote:
>>> For my eventual move to Oz, I will be building my own motor/generator to
>>> power those tools that cannot be converted to 3phase. Don't plan to run
>>> many items at once, I'm thinking about maybe a 4kw generator.
>>>
>>> What's a good reliable generator at the output end? Going to try to find
>>> one with a bad engine, but want to make sure the other half will last a
>>> while given the expense of having a replacement shipped over....
>>> And yeah, I'm planning on taking spare parts for it.
>>>
>>> Jon
>>
>>I think you are looking for something like this.
>>
>>http://cgi.ebay.com/NEW-ST-10KW-GENERATOR-HEAD-1-Phase-Diesel-Gas-Engine_W0QQitemZ220513914951QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item3357a75047
>>
>>Search on " generator head ST "
>>
>>However these are made in China and are probably available in
>>Australia.
>>
>> Dan
>
>Stick a small car engine on it with a belt idling at 900 rpm and a 1:2
>pully ratio and one is golden.


Nope, Sorry - It would work but not well.

900 RPM is just off idle for a gasoline engine and not much more
than that for a small diesel, and way out of the powerband. You would
need a way oversized engine to get maximum output, and at lousy fuel
efficiency.

1800 RPM is the sweet spot for medium and larger diesels, and gives
you the best efficiency - many of the big truck and industrial engines
for gensets have a 2400 to 3500 RPM red-line.

1800 RPM would be practical for small automotive gasoline engines to
get maximum life, even if you have to derate because it's still way
south of the torque peak.

The big honkers like the GM EMD 567 - 645 - 710 locomotive diesels are
all redlined between 800 and 900 RPM, but then again we're talking 600
HP to 5,000 HP.

--<< Bruce >>--

Gunner Asch

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Nov 23, 2009, 3:46:03 AM11/23/09
to

Most car engines are far far more than 15 hp, no?

Ive kinda sorta played with this in the past..and gallons per hour at
idle, in a clean warmed up engine isnt piddly.


>
> 1800 RPM is the sweet spot for medium and larger diesels, and gives
>you the best efficiency - many of the big truck and industrial engines
>for gensets have a 2400 to 3500 RPM red-line.

Hence the 1:2 pullys. Idle at 900 rmp..turn the genny at 1800.


>
>1800 RPM would be practical for small automotive gasoline engines to
>get maximum life, even if you have to derate because it's still way
>south of the torque peak.

Can you provide some gallons per hour figures for small car engines at
900rpm and 1800 rpm?

Id be most interested to read them.

>
>The big honkers like the GM EMD 567 - 645 - 710 locomotive diesels are
>all redlined between 800 and 900 RPM, but then again we're talking 600
>HP to 5,000 HP.

Indeed.
>
>--<< Bruce >>--

jbsl...@gmail.com

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Nov 23, 2009, 7:10:01 AM11/23/09
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On Sun, 22 Nov 2009 23:22:06 -0600, RoyJ <spam...@microsoft.net>
wrote:

>Not really. An 1800 rpm generator will be a 4 pole unit, a 3600 rpm
>generator will be a 2 pole unit. A 4 pole, 1800 rpm unit is usually
>MUCH quieter than the 2 pole versions. And engine life at 1800 rpm is on
>the order of 5x to 10x the life at 3600 rpm.

Yes, if you want 60 Hz at 1800 RPM you use a four coil machine, etc.,
but the generator itself doesn't care a bit about whet RPM it spins
at. You can run a 4 pole generator at 1000, 1800 or even 3,000 RPM
(assuming that the machine was properly made) and it is perfectly
happy to produce electricity. As I said, it doesn't care and it
certainly doesn't make any more noise at high RPM then it does at slow
speeds.

Most generators made today use non-friction bearings and if kept
lubricated will last for years and the RPM is nearly meaningless to
them.

You will note that when I use the term "generator" I am talking about
the electrical generating device.

And as I said, the 1800/3600 RPM thing was mainly about engine life
and noise.

>> Mechanically the generator itself doesn't care what RPM it turns at,
>> Other then possibly accelerated bearing wear which is minimal with
>> ball/roller bearings. The gumph about 1800 RPM vis-a-vis 3600 was
>> mostly heard from the marine users and was mainly worry about engine
>> life and noise.
>>
>> Regards,
>>
>> J.B.

Regards,

J.B.

jbsl...@gmail.com

unread,
Nov 23, 2009, 7:14:24 AM11/23/09
to
On Mon, 23 Nov 2009 00:18:52 -0800, Bruce L. Bergman
<bruceNOSP...@gmail.com> wrote:


Err, say 3700 Kw? A bit more then he really needs for his shop....

Regards,

J.B.

RoyJ

unread,
Nov 23, 2009, 9:19:54 AM11/23/09
to
If you want 60 HZ like the OP, then you MUST run a 4 pole at 1800 RPM
and a 2 pole at 3600rpm. Not to mention, the windings are designed to
produce a specific voltage at those speeds. If all you want is junk
power output with no voltage OR frequency regulation, run them at other
speeds.

Michael A. Terrell

unread,
Nov 23, 2009, 3:30:05 PM11/23/09
to

Gunner Asch wrote:
>
> On Sun, 22 Nov 2009 06:15:06 -0800 (PST), "dca...@krl.org"
> <dca...@krl.org> wrote:
>
> >On Nov 21, 5:59 pm, Jon Anderson <janders1...@comcast.net> wrote:
> >> For my eventual move to Oz, I will be building my own motor/generator to
> >> power those tools that cannot be converted to 3phase. Don't plan to run
> >> many items at once, I'm thinking about maybe a 4kw generator.
> >>
> >> What's a good reliable generator at the output end? Going to try to find
> >> one with a bad engine, but want to make sure the other half will last a
> >> while given the expense of having a replacement shipped over....
> >> And yeah, I'm planning on taking spare parts for it.
> >>
> >> Jon
> >
> >I think you are looking for something like this.
> >
> >http://cgi.ebay.com/NEW-ST-10KW-GENERATOR-HEAD-1-Phase-Diesel-Gas-Engine_W0QQitemZ220513914951QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item3357a75047
> >
> >Search on " generator head ST "
> >
> >However these are made in China and are probably available in
> >Australia.
> >
> > Dan
>
> Stick a small car engine on it with a belt idling at 900 rpm and a 1:2
> pully ratio and one is golden.


Agtronics used to make 900 RPM PTO driven generators, but I think
they are long gone.


--
The movie 'Deliverance' isn't a documentary!

Don Foreman

unread,
Nov 24, 2009, 12:26:53 AM11/24/09
to
On Mon, 23 Nov 2009 00:46:03 -0800, Gunner Asch
<gun...@NOSPAMlightspeed.net> wrote:


>
>Can you provide some gallons per hour figures for small car engines at
>900rpm and 1800 rpm?
>
>Id be most interested to read them.
>

Such data would be meaningless without a specified mechanical load. An
engine under load at X rpm uses more fuel than one just idling at that
same RPM.

Bruce L. Bergman

unread,
Nov 24, 2009, 2:05:38 AM11/24/09
to

Heck, I'd have to go back and look, but I know the 16-cylinder
turbocharged 710 series was hitting at least 1.5 MW, some IIRC were
pushing towards 2 MW. Serious freight locomotives.

Then again, there were far bigger - like the Union Pacific 4-8-8-4
"Big Boy" steam engines with an articulated frame.

And the later incarnation of "huge" being the Union Pacific "Big Blow"
GTEL gas turbine-electrics - 8,500 HP (6.3 MW) each, later upgraded to
10,000 HP (7.5 MW)

A big enough set of jumper cables, and you can run a good sized city
with that puppy. Can't hear yourself think for about a mile radius,
though, with an unmuffled gas turbine exhaust aimed straight up at
full throttle...

Oh, and bring lots of heavy Bunker-C fuel oil...

--<< Bruce >>--

Bruce L. Bergman

unread,
Nov 24, 2009, 2:14:14 AM11/24/09
to
On Mon, 23 Nov 2009 00:46:03 -0800, Gunner Asch

<gun...@NOSPAMlightspeed.net> wrote:
>On Mon, 23 Nov 2009 00:18:52 -0800, Bruce L. Bergman
><bruceNOSP...@gmail.com> wrote:
>>On Sun, 22 Nov 2009 14:04:08 -0800, Gunner Asch
>><gun...@NOSPAMlightspeed.net> wrote:

>>>Stick a small car engine on it with a belt idling at 900 rpm and a 1:2
>>>pully ratio and one is golden.
>>
>> Nope, Sorry - It would work but not well.
>>
>> 900 RPM is just off idle for a gasoline engine and not much more
>>than that for a small diesel, and way out of the powerband. You would
>>need a way oversized engine to get maximum output, and at lousy fuel
>>efficiency.
>
>Most car engines are far far more than 15 hp, no?
>
>Ive kinda sorta played with this in the past..and gallons per hour at
>idle, in a clean warmed up engine isnt piddly.

Oh it would work, I'll grant you that. But not all that well.
Gasoline engines can't hold a candle to a diesel for longevity.

Better to get one of the surplus 3-cylinder or 4-cylinder Kubota or
Yanmar diesels made for truck reefers. They can run for years with
normal maintenance, and either rebuilt or replaced when worn out.



>> 1800 RPM is the sweet spot for medium and larger diesels, and gives
>>you the best efficiency - many of the big truck and industrial engines
>>for gensets have a 2400 to 3500 RPM red-line.
>
>Hence the 1:2 pullys. Idle at 900 rmp..turn the genny at 1800.

Yes, but you need a lot of belt there - a triple or a quad sheave.
And you need a generator wend with two bearing, and the front bearing
has to be rated for the side-thrust of the belt drive.

--<< Bruce >>--

Gunner Asch

unread,
Nov 24, 2009, 2:16:43 AM11/24/09
to

Indeed it does. So it would be very interesting to determine what
that 15hp genset would actually cost a 125hp engine in fuel at an
idle, no? Even a VW engine at 47 hp.

Gunner

Gunner Asch

unread,
Nov 24, 2009, 2:34:13 AM11/24/09
to
On Mon, 23 Nov 2009 23:14:14 -0800, Bruce L. Bergman
<bruceNOSP...@gmail.com> wrote:

>On Mon, 23 Nov 2009 00:46:03 -0800, Gunner Asch
><gun...@NOSPAMlightspeed.net> wrote:
>>On Mon, 23 Nov 2009 00:18:52 -0800, Bruce L. Bergman
>><bruceNOSP...@gmail.com> wrote:
>>>On Sun, 22 Nov 2009 14:04:08 -0800, Gunner Asch
>>><gun...@NOSPAMlightspeed.net> wrote:
>
>>>>Stick a small car engine on it with a belt idling at 900 rpm and a 1:2
>>>>pully ratio and one is golden.
>>>
>>> Nope, Sorry - It would work but not well.
>>>
>>> 900 RPM is just off idle for a gasoline engine and not much more
>>>than that for a small diesel, and way out of the powerband. You would
>>>need a way oversized engine to get maximum output, and at lousy fuel
>>>efficiency.
>>
>>Most car engines are far far more than 15 hp, no?
>>
>>Ive kinda sorta played with this in the past..and gallons per hour at
>>idle, in a clean warmed up engine isnt piddly.
>
> Oh it would work, I'll grant you that. But not all that well.
>Gasoline engines can't hold a candle to a diesel for longevity.
>
> Better to get one of the surplus 3-cylinder or 4-cylinder Kubota or
>Yanmar diesels made for truck reefers. They can run for years with
>normal maintenance, and either rebuilt or replaced when worn out.

Now thats an excellent thought!! Buddy of mine is moving to
Idaho..bought a nice trailer..Fruehoff I think for $2500, has the
reefer on the front.

>
>>> 1800 RPM is the sweet spot for medium and larger diesels, and gives
>>>you the best efficiency - many of the big truck and industrial engines
>>>for gensets have a 2400 to 3500 RPM red-line.
>>
>>Hence the 1:2 pullys. Idle at 900 rmp..turn the genny at 1800.
>
> Yes, but you need a lot of belt there - a triple or a quad sheave.
>And you need a generator wend with two bearing, and the front bearing
>has to be rated for the side-thrust of the belt drive.
>
>--<< Bruce >>--

Ive seen several of them done this way...and they used two belts.
period. Worked quite well and for a very long time. I believe one
engine was a VW from a bug and the other was from a Chevy Luv..best as
I can recall.

Lots of small ranches/trailers out in the desert up against the
Temblor Range...not much power.

Gunner

dca...@krl.org

unread,
Nov 24, 2009, 8:05:04 AM11/24/09
to
On Nov 24, 7:16 am, Gunner Asch <gun...@NOSPAMlightspeed.net> wrote:

> Indeed it does.  So it would be very interesting to determine what
> that 15hp genset would actually cost a 125hp engine in fuel at an
> idle, no?  Even a VW engine at 47 hp.
>
> Gunner

If I were going to do something like that, I would be thinking
converting a propane forklift engine to natural gas and using the hot
water to heat the house and/or workshop. Engines run on natural gas
run a long time and I expect natural gas would be cheaper than diesel.

Dan

Gunner Asch

unread,
Nov 24, 2009, 8:28:08 AM11/24/09
to


Indeed. Ive seen that done before.

And the engine itself used to run a genny for electrical power.


Gunner

AdeV

unread,
Nov 24, 2009, 10:31:42 AM11/24/09
to
Gunner Asch may or may not have intoned:

> On Mon, 23 Nov 2009 00:18:52 -0800, Bruce L. Bergman
> <bruceNOSP...@gmail.com> wrote:
>
> >On Sun, 22 Nov 2009 14:04:08 -0800, Gunner Asch
> ><gun...@NOSPAMlightspeed.net> wrote:
> >
> >>Stick a small car engine on it with a belt idling at 900 rpm and a 1:2
> >>pully ratio and one is golden.
> >
> >
> > Nope, Sorry - It would work but not well.
> >
> > 900 RPM is just off idle for a gasoline engine and not much more
> >than that for a small diesel, and way out of the powerband. You would
> >need a way oversized engine to get maximum output, and at lousy fuel
> >efficiency.
>
> Most car engines are far far more than 15 hp, no?
>
> Ive kinda sorta played with this in the past..and gallons per hour at
> idle, in a clean warmed up engine isnt piddly.

I have to side with Bruce on this one: I know, because I've done
something pretty similar. Build a 6KVA generator using a 1.8ltr petrol
4-cyl (gas) engine. Engine speed was set at 1200rpm, for a generator
speed of 3600 IIRC.

The results were lousy. The engine couldn't hold a steady speed even
when the load was constant, let alone when loads came on & off. Warmup
was a bitch (choke + throttle control).

Replaced it with a 1.6 diesel lump, which solved all of the above
problems. The only issue we have now is it keeps burning out the glow
plugs (software issue).

--
Cheers!
Ade.

Karl Townsend

unread,
Nov 28, 2009, 8:20:39 AM11/28/09
to

"Jon Anderson" <jande...@comcast.net> wrote in message
news:fUVNm.62201$Vr1....@en-nntp-01.dc1.easynews.com...

> For my eventual move to Oz, I will be building my own motor/generator to
> power those tools that cannot be converted to 3phase. Don't plan to run
> many items at once, I'm thinking about maybe a 4kw generator.
>
> What's a good reliable generator at the output end? Going to try to find
> one with a bad engine, but want to make sure the other half will last a
> while given the expense of having a replacement shipped over....
> And yeah, I'm planning on taking spare parts for it.
>
>
> Jon

A little late on the reply, but take a look at this:
http://cgi.ebay.com/New-12-kW-PTO-Tractor-Driven-PTO-Generator-540-RPM_W0QQitemZ390122766369QQcmdZViewItemQQptZBI_Generators?hash=item5ad5210021

looks easy to take the PTO part off and use a small engine also.

Karl


Gunner Asch

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Nov 28, 2009, 7:34:45 PM11/28/09
to


Oh veddy veddy nice!

Bruce L. Bergman

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Nov 30, 2009, 1:47:38 AM11/30/09
to
On Sat, 28 Nov 2009 16:34:45 -0800, Gunner Asch
<gun...@lightspeed.net> wrote:
>On Sat, 28 Nov 2009 07:20:39 -0600, "Karl Townsend"
><karltown...@embarqmail.com> wrote:
>>"Jon Anderson" <jande...@comcast.net> wrote in message
>>news:fUVNm.62201$Vr1....@en-nntp-01.dc1.easynews.com...

>>> For my eventual move to Oz, I will be building my own motor/generator to
>>> power those tools that cannot be converted to 3phase. Don't plan to run
>>> many items at once, I'm thinking about maybe a 4kw generator.
>>>
>>> What's a good reliable generator at the output end? Going to try to find
>>> one with a bad engine, but want to make sure the other half will last a
>>> while given the expense of having a replacement shipped over....
>>> And yeah, I'm planning on taking spare parts for it.
>>>
>>>
>>> Jon
>>
>>A little late on the reply, but take a look at this:
>>http://cgi.ebay.com/New-12-kW-PTO-Tractor-Driven-PTO-Generator-540-RPM_W0QQitemZ390122766369QQcmdZViewItemQQptZBI_Generators?hash=item5ad5210021
>>
>>looks easy to take the PTO part off and use a small engine also.
>>
>>Karl
>
>Oh veddy veddy nice!
>
>Gunner

You could get a small Cummins or Cat implement diesel to do 540 RPM
directly, but it would have to be rated a lot higher than 20 HP -
that's figuing on a tractor with a 3:1 or 4:1 PTO reduction so the
engine is up in the powerband while running threshers and other PTO
powered implements. Then the gearbox on the generator steps the PTO
shaft speed back up to 1800 RPM for the generator head.

You need an engine rated in the 40 - 50 HP range, so you can get 20 HP
worth of output when you direct-couple it and loaf along at 540 RPM.

--<< Bruce >>--

Gunner Asch

unread,
Nov 30, 2009, 5:07:57 AM11/30/09
to

Or simply a small pully on the engine..and a bigger one on the genny.

That would get the engine size down to the small cummins range.

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